RESUMO
Many new plant proteins are appearing on the market, but their properties are insufficiently characterized. Hence, we collected 24 commercial proteins from pea, oat, fava bean, chickpea, mung bean, potato, canola, soy, and wheat, including different batches, and assessed their techno-functional and sensory properties. Many powders had yellow, red, and brown color tones, but that of fava bean was the lightest. The native pH ranged from 6.0 to 7.7. The water solubility index was 28% on average, but after heat treatment the solubility typically increased. Soy isolate had by far the best water-holding capacity of 6.3 g (H2O) g-1, and canola had the highest oil-holding capacity of 2.8 g (oil) g-1. The foaming capacity and stability results were highly varied but typical to the raw material. The emulsification properties of all powders were similar. Upon heating, the highest viscosity and storage modulus were found in potato, canola, and mung bean. All powders had raw material flavor, were bitter and astringent, and undissolved particles were perceived in the mouth. Large differences in functionality were found between the batches of one pea powder. In conclusion, we emphasize the need for methodological standardization, but while respecting the conditions found in end applications like meat and dairy analogs.
RESUMO
Plant materials that are used for the production of extruded meat analogs are often nutritionally incomplete and also contain antinutrients, thus there is a need to explore alternative plant proteins and pre-treatments. This study demonstrates application of phytase and fermentation to a pea-oat protein blend with a good essential amino acid profile and subsequent texturization using extrusion cooking. Enzymatic treatment reduced the content of antinutrient phytic acid by 32%. Extrusion also degraded phytic acid by up to 18%, but the effect depended on the material. Differences in physicochemical, sensorial, and textural properties between untreated and phytase-treated extruded meat analogs were small. In contrast, fermented material was more difficult to texturize due to degradation of macromolecules; physicochemical and textural properties of extrudates were markedly different; sensory analysis showed enhancement of flavor, but also detected an increase in some unwanted taste attributes (bitterness, cereal and off-taste). Phytic acid was not degraded by fermentation. Analysis of volatile compounds showed extrusion eliminated volatiles from the raw material but introduced Maillard reaction products. Overall, phytase treatment and fermentation demonstrated the potential for application in extruded meat analogs but also highlighted the necessity of optimization of process conditions.
RESUMO
Pea protein dry-fractionated (PDF), pea protein isolated (PIs), soy protein isolated (SIs) and oat protein (OP) were combined in four mixes (PDF_OP, PIs_OP, PDF_PIs_OP, SIs_OP) and extruded to produce meat analogues. The ingredients strongly influenced the process conditions and the use of PDF required higher specific mechanical energy and screw speed to create fibrous texture compared to PIs and SIs. PDF can be conveniently used to produce meat analogues with a protein content of 55 g 100 g-1, which is exploitable in meat-alternatives formulation. PDF-based meat analogues showed lower hardness (13.55-18.33 N) than those produced from PIs and SIs (nearly 27 N), probably due to a more porous structure given by the natural presence of carbohydrates in the dry-fractionated ingredient. PDF_OP and PIs_PDF_OP showed a significantly lower water absorption capacity than PIs OP and SIs_OP, whereas pea-based extrudates showed high oil absorption capacity, which could be convenient to facilitate the inclusion of oil and fat in the final formulation. The sensory evaluation highlighted an intense odor and taste profile of PDF_OP, whereas the extrudates produced by protein isolates had more neutral sensory characteristics. Overall, the use of dry-fractionated protein supports the strategies to efficiently produce clean-labeled and sustainable plant-based meat analogues.